TASK_1  Write a function DELETE_LOWERCASE , which removes all lowercase letters,
from the string of characters (given as input to this function).

TASK_2  Write the function COMPARE_LOWER_UPPER checking whether in the text (given as an argument)
there are more lowercase or uppercase letters. Depending on the results of the comparison,
the function should return a number: positive, negative or zero.

TASK_3  Write the DELETE_DOUBLE_SPACES function that deletes all "multiple spaces" ,
from the text given as a parameter.

TASK_4  Write the function DELETE_FIRST_MINUS
removing (by shortening the text) the first occurrence of the minus character  '–' ,
from the string of characters passed as input to this function.

TASK_5  Write a function ADD_5_SPACES which adds 5 spaces to the beginning of the text,
passed as an input parameter of this function.

TASK_6  Write the function DELETE_COMMENT which deletes (from the text passed as a parameter)
the second part of the string, starting with the comment "//" sequence.

TASK_7  Write a function that HAS_TXT_EXTENSION checking whether the text (passed as a parameter of this function)
ends with the sequence ".txt" (just like the names of text files).

1. Write a function, DELETE_LOWERCASE , which removes all lowercase letters,
   from the string of characters (given as input to this function).

char* DELETE_LOWERCASE( char t[]) {    int i = 0;    while (t [i]! = '\ 0')    if (t [i]> = 'a' && t [i] <= 'z')      strcpy ( &t[i], &t[i + 1]);    else      i++;    return t; }

// the second (faster) version of the same function char* DELETE_LOWERCASE_2( char t[]) {    int i=0, j=0;    while( t[i] != '\0' )      if( t[i]>='a' && t[i]<='z' )        i++;      else        t[j++] = t[i++];    t[j] = '\0';    return t; }

2. Write the function COMPARE_LOWER_UPPER checking whether in the text (given as an argument)
   there are more lowercase or uppercase letters. Depending on the results of the comparison,
   the function should return a number: positive, negative or zero.
   

int COMPARE_LOWER_UPPER( char t[]) {   int counter_lower=0, counter_upper=0;   for( int i=0; t[i] != '\0'; i++)     {       if( t[i]>='a' && t[i]<='z')         counter_lower++;       if( t[i]>='A' && t[i]<='Z')         counter_upper++;     }   return counter_lower - counter_upper; }   #include <stdio.h> using namespace std; int main () // example program, using the above function, {           // with text loaded from the keyboard   char text[100];   printf( "Enter a text to check:" );   fgets( text, 100, stdin );   int result = COMPARE_LOWER_UPPER(text);   if( result>0 )     printf( "more lowercase letters" );   else if( result<0 )     printf( "more uppercase letters" );   else     printf( "there are as many lowercase as uppercase" );   return 0; }

3. Write the DELETE_DOUBLE_SPACES function that deletes all "multiple spaces" ,
   from the text given as a parameter.

char* DELETE_DOUBLE_SPACES( char t[] ) {   if( t[0] == '\0' || t[1] == '\0')     return t;   int i = 1;   while( t[i] != '\0' )     if( t[i-1]==' ' && t[i]==' ' )       strcpy( &t[i], &t[i+1] );     else       i++;   return t; }

4. Write the function DELETE_FIRST_MINUS
   removing (by shortening the text) the first occurrence of the minus character  '–' ,
   from the string of characters passed as input to this function.

#include <string.h> void DELETE_FIRST_MINUS( char t[] ) {    int position=0;   // search for first '-' character   while( t[position]!=0 && t[position]!='-' )     ++position;   // delete the character (if found)   if( t[position]=='-' )     strcpy( &t[position], &t[position+1] ); }

5. Write a function ADD_5_SPACES which adds 5 spaces to the beginning of the text,
   passed as an input parameter of this function.

#include <string.h> void ADD_5_SPACES( char t[] ) {   // shift all letters, 5 positions to the right   memmove( t+5, t, strlen(t)+1 );   // fill the beginning with spaces   for( int i=0; i<5; i++ )     t[i]=32; }

6. Write the function DELETE_COMMENT which deletes (from the text passed as a parameter)
   the second part of the string, starting with the comment "//" sequence.

#include <string.h> void DELETE_COMMENT ( char t[] ) {   // find the position of the comment characters   char* wsk;   wsk = strstr( t, "//" );   // trimming the right fragment, starting from the found position   if( wsk!=NULL )     *wsk=0; }

7. Write a function that HAS_TXT_EXTENSION checking whether the text (passed as a parameter of this function)
   ends with the sequence ".txt" (just like the names of text files).

#include <string.h> int HAS_TXT_EXTENSION( char name[] ) {   int length = strlen (name);   // immediate return, if the name has less than 4 letters   if (length <4)     return 0; // return false   // check, if the last four letters are ".txt"   if( strcmp( name+length-4, ".txt" )==0 )     return 1; // return true   else     return 0; }